chrise chrise - 2 months ago 15
C++ Question

c++ cannot use libraries in other libraries

I added some libraries, both shared and static and got them to work so that I can use them in a desktop application. However, when I try to use a static library in another static library or a shared library in another shared library that does not seem to work.
I get the error Cannot open include file mylibrary.h: no such file or directory

Is there a way around it? If not, what is the best way to structure projects/libraries. It seems to be very limiting that that libraries cant use other libraries

This is my application's .pro where I can use he library

QT += core
QT -= gui

CONFIG += c++11

TARGET = Test
CONFIG += console
CONFIG -= app_bundle

TEMPLATE = app

SOURCES += main.cpp

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../SharedLib/release/ -lSharedLib
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../SharedLib/debug/ -lSharedLib

INCLUDEPATH += $$PWD/../SharedLib
DEPENDPATH += $$PWD/../SharedLib

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../SharedLib_2/release/ -lSharedLib_2
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../SharedLib_2/debug/ -lSharedLib_2

INCLUDEPATH += $$PWD/../SharedLib_2
DEPENDPATH += $$PWD/../SharedLib_2


and the .pro of SharedLib which is supposed to use SharedLib_2

QT -= gui

TARGET = SharedLib
TEMPLATE = lib

DEFINES += SHAREDLIB_LIBRARY

SOURCES += sharedlib.cpp

HEADERS += sharedlib.h\
sharedlib_global.h

unix {
target.path = /usr/lib
INSTALLS += target
}

win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../SharedLib_2/release/ -lSharedLib_2
else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../SharedLib_2/debug/ -lSharedLib_2

INCLUDEPATH += $$PWD/../SharedLib_2
DEPENDPATH += $$PWD/../SharedLib_2


I added them both via the automatic add library and the lines are identically... so I would have expected this to work

includes are

application

#include <QCoreApplication>

#include "sharedlib.h"
#include "sharedlib_2.h"

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);

SharedLib sl;
SharedLib_2 sl_2;

return a.exec();
}


sharedLib

#include "sharedlib.h"

#include "sharedlib_2.h" // ERROR HERE

SharedLib::SharedLib()
{
}

Answer

Your INCLUDEPATH looks OK, so probably the problem is in the old Makefile. You should run qmake to generate proper Makefile for your updated .pro file.

Go to Build -> Run qmake in QT Creator to do that.